Bat friends, monkeys sharing, and humans holding hands: the brains of social animals synchronise and expand one another
Sofia Quaglia is a freelance science reporter, writing about the environment, health and the mind. Her work has been published in The Guardian, BBC and National Geographic, among others.
Humans are not the only creatures that show a refined grasp of social norms. If a group of adult male rhesus monkeys (Macaca mulatta) find themselves sitting around a turning table set with food, they will display an ‘I scratch your back, you scratch mine’ ethos of reciprocity. One monkey will offer another one a piece of fruit and, what’s more, will expect the gesture to be reciprocated. If the offer isn’t forthcoming, the first monkey is likely to retaliate by refusing to give up anything on his turn. The monkeys also like to group together in cliques; if they see one monkey has been kind to another, they collectively show kindness to the first monkey. If you’re observing, it looks like nothing so much as a group of friends buying each other rounds of drinks at a bar.
While decades of research have dispelled the myth that sociality is unique to our species, scientists are still unclear about just how individual animals retain information about the structure of the ‘society’ in which they’re embedded. Are the monkeys simply copying each other and sharing food via a sophisticated form of mirroring? Or are they truly keeping track of their own and others’ behaviour in order to make decisions within a broader social dynamic?
Over the years, biologists have used a variety of lenses to try and answer these sorts of questions. While 19th-century naturalists looked at animal behaviour with a focus on its psychological and physiological aspects, it was only after the groundbreaking work of zoologists such as Nikolaas Tinbergen and Karl von Frisch in the 1930s that the field returned to a focus on how social behaviour might be explained in evolutionary terms.
Following the emergence of the modern discipline of ethology – the study of animal behaviour – we’ve been left with two main ways of framing enquiries into the social lives of animals. One approach takes data from observations of animals in the field, trying to understand the group dynamic by looking from the ‘outside in’. Yet this necessarily makes it hard to fathom what’s happening inside an individual creature’s mind. By contrast, the second approach is based on detecting an individual’s brain activity, and then on trying to draw a map between patterns of neuronal spiking or firing – the oscillating electrical activity that produces brain waves – and how the animal acts. Yet this data comes from the ‘inside out’, and often struggles to encompass group dynamics. Both of these frames tend to capture an incomplete picture.
Now a new generation of scientists is pushing for a third, more nuanced paradigm for studying animal sociality. Known as ‘collective neuroscience’, this research programme proceeds from the idea that brains have evolved primarily to help animals exist as part of a social group – rather than to solve problems per se – and should be studied as such. Since embedding a brain within a social structure changes how it and other brains perform, it makes no sense to only study individual minds in isolation, because it doesn’t provide the full picture. Based on the notion that intelligence is a dynamic of looping cause and effect among multiple brains, researchers are drawing on the latest neuroimaging techniques to try to obtain a more detailed understanding of multiple animals’ brain states as they engage in a variety of social activities. The hope is that this could lead us to answers about how animals perceive their social world, and how that perception is neurally encoded.
Beyond nonhuman animals, collective neuroscience could also help us decipher some of the complexities of human society as well. Since brains appear to work differently when placed in relationships with others, we might begin to recognise the necessity to tailor interventions to improve mental health in terms of the wider social environment, rather than focusing on individual pathologies. And, in quite a different domain, if sociality is a necessary step on the road to intelligence, it’s unclear whether machine-learning algorithms really stand a chance of approximating a human intellect – unless they’re embedded in a rich society of other algorithms.
In mainstream approaches to cognitive neuroscience in animals, portions of the brain are labelled as relating to perception, action, memory, attention, decision, sociality. But when we examine animal behaviour through a more collective lens, we begin to see that large portions of complex brains are hungry to work in harmony with others, according to Emmanuelle Tognoli, a researcher at the Center for Complex Systems and Brain Sciences at Florida Atlantic University…